But does that mean our human future is doomed? Today, many of the most-read publications and most-shared tweets on the climate crisis predict extinction, and a new survey of young people in 10 countries shows that most of them agree. Climate “doomism” holds that greenhouse gas emissions are soaring beyond control, that runaway heating will continue even if emissions decline, and that ecosystems, then societies, will collapse once heating exceeds thresholds that will soon be reached.
It’s a terrifying thought. But it’s wrong — and dangerous.
To explain why, it’s worth repeating a simple truth: The future of climate change depends, first, on human-generated greenhouse gas emissions and, second, on the sensitivity of Earth’s climate to those emissions.
Let’s start with emissions. Owing in large part to the plummeting cost of solar and wind power, they have plateaued, and should soon begin to decline. Scenarios that forecast soaring emissions, considered likely only a few years ago, now seem implausible.
Yet Earth’s sensitivity to those emissions is so high that, if policies and technologies remain as they are, by century’s end Earth will probably warm by close to three degrees Celsius. Warming of this magnitude, with this speed, could strengthen feedback loops in Earth’s environment that cause still more warming. Heat waves would dry up forests, for example, increasing the likelihood of wildfires that release additional carbon dioxide into the atmosphere, causing more warming, more burning, and so on.
But there’s good news. Emissions — not feedbacks — will probably determine the temperature of the Earth by the end of this century. New research suggests that if we stop releasing more greenhouse gases than environments — and perhaps new technologies — can absorb, the Earth will soon stop warming. How soon would depend on whether we also stop emitting aerosol pollutants and on natural variability in the Earth’s climates. Yet we are not committed to a much hotter future.
“Doomism” also holds that even small changes in average weather have toppled past societies. Some historical societies did indeed suffer when climates changed for natural causes (more modestly than they undoubtedly will this century). Yet the idea of an ideal climate for civilization is based on centuries-old, racist assumptions that only Europe and North America were well suited for human development. Today, research in many fields finds that societies often adapted to past climate changes, and few collapsed. Some societal adaptations were counterintuitive; when land sank relative to sea levels, for example, populations repeatedly gathered near the coast.
In recent years, a new generation of activists has finally forced the climate crisis to the forefront of public debate and legislation. Climate policies have been drafted or are being implemented on a scale that once seemed unimaginable. It is not enough, and large-scale efforts to adapt to climate change are only in their infancy. Yet it is beginning to feel possible that the climate crisis can be overcome.
Doomism threatens to derail this progress. What use is fighting if the battle is already lost? Why advance any righteous cause — racial justice, a fair economy, a healthy democracy — when the climate apocalypse is right around the corner? Doomism encourages apathy — and those who benefit are the very corporations and political extremists most responsible for the environmental and social problems we face.
Doomism may be increasingly popular, but so is its equally implausible opposite: the belief that economic growth and technological innovation will increase wealth and security more quickly than climate change can diminish them. According to that view, even extreme emissions scenarios are nothing to worry about.
Yet the most likely future is one that lands between these extremes. In it, emissions decline but not as quickly as they should; warming reaches dangerous highs, but doesn’t overwhelm our capacity for adaptation. It is this future that demands we act urgently. We must cut emissions more quickly than they’re on pace to fall; we must realize our adaptive capacities. The future of the planet, and of humanity, is at stake.